SO2 SO3 emissions

Scrubbing is often accomplished by either wet or dry scrubbing. I am more familiar with wet scrubbing, which is accomplished using limestone slurries for large applications and sodium hydroxide for small applications. The methodology of scrubbing towers varies from baffled columns (NaOH method) to large counter-current limestone spray towers. Another option is a Dynawave scrubber by MECS, which is a designed reverse jet scrubber. Most scrubbers operate from 7-9 pH. Higher pH will begin to scrub CO2 vapors as well. Lower pHs tend to start losing efficiency as you begin to approach the pKa of the resulting salt.

Depending on design, efficiencies greater than 99% can be achieved, though high efficiency is easier with NaOH (expensive) than lime (cheap).

Look up flue-gas desulfurization processes as a starter. There is a large amount of existing literature on this.

Oh, and when scrubbing SO2, you’ll need to further oxidize the resulting sulfite ion to sulfate to prevent chemical oxygen demand as well as potential re-release of SO2 if solution pH drops.

Hi,
Consider the resource attached .
Note : you should consult your local EPA for the limits in your area.
Pierre

Hi,
Alternative process , using sodium bicarbonate :

Pierre

To better assess what is the most practical pollution control technology, one would have to know the volume of gas that you propose to discharge.